July 2013

​Parasite on a lab rat

This hair was plucked from a laboratory rat in a colony used to study animal behavior. What type of insect is present?

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Answer:

This is an anopluran, or sucking louse (Polyplax sp.). Lice are host specific and complete their entire life cycle on the host; transmission is by direct contact between hosts. The heads of anoplurans, designed to suck blood, are typically narrower than the thorax and have protruding mouthparts. Attached to the hair shaft shown here are louse eggs, or nits. In heavy infestations, some anoplurans, including Polyplax sp., can cause anemia.​Case and photo provided by Oklahoma State University veterinary student Heather Rhoden.